Technical Very worn rocker ball pivot

I tried the Comp Cams roller tip rockers on my 283 in the '55 that I assembled in '14. Duntov 098 solid cam. I've been building Chevy small blocks since the early '60s and never had a problem with stock rockers. The valve lash would open up after driving arround for a few miles. Reset the lash and again it would open up. Pulled all the rockers off and all the pushrods were ground down by the ball sockets in the rockers. There was a sharp ridge in all the rocker sockets that was a failure of a quality control check. Fortunately I caught it before the bearings were damaged. As Johnny Gee did I replaced them with quality full roller rockers. I set the lash ten years ago and check it once a year, it hasn't changed. An old engine builder friend said his opinion on roller tip rockers is that the greatest amount of friction is in the pivot ball not the valve stem. I'd run stock Chevy rockers before using the roller tip. I have three running small blocks and a 327 that is on my engine stand, all have full roller rockers.

 

Take a stock rocker and ball in your hand and replicate motion, smooth. Now do the same with the Comp roller tip unit. Clunk clunk.

 

That rocker cup where the ball sits appears quite rough. It should be polished smooth look. Somewhere is mismatched parts or faulty part.

 

New parts, as in anything over a quantity if ONE... I line them up and give them the once over. Real odd parts should be obvious if you take some time with them. Heck... I even measure every push rod in a set of 16 to make sure they all match.

One guy in the 'hood, big Mopar freak. He just had a push rod to roller rocker arm galling problem. I looked over the push rods and found a couple that had serious burrs on one end.

 

Thanks for the pics. The rocker in question definitely got toasty. Given that these pivots are PM, how even the wear is and how little wear is on the laying rocker surface, I would agree with @Fordors in suspecting this pivot was not sintered correctly in the first place.
I agree with the rollerized pivot being much more beneficial than the roller tip.

 

If you ran it across a file and got metal shavings it’s not hardened.

 

There is no way that rocker ball can wear that much. Its the wrong one from a different engine or cam.

 

You can nick a PM part with a file but it will not give shavings. And also, PM can be hardened in the cooling zone of the furnace by cooling the material more rapidly but for this application I doubt that was done.

 

Update. Got a new pivot ball on the bad rocker (#7 exhaust)

Started it up, ran a little rough

Oil fill cap is conveniently located above #7 so looked thru and saw no oil moving around on those rockers

Pulled VC, all other rockers on that side had oil pooled in them.

Started engine, no oil coming to intake and exhaust on rockers on 7 and within 5 seconds of running the rocker hopped off intake on 7, pushrod dropped down an inch or so

The worn ball pivot was on the exhaust on 7

 

If you use an engine pre-oiling tool, you won't have to actually start the engine, risking damage.

I'd swap the rockers and balls off #7 with another (known good) cylinder (after drying the rockers) and see if the problem moves to the new location.

Did you verify the rocker oiling holes aren't plugged?

Do you have the set of factory rockers still available?

 

Rocker holes are clear and in correct position. Push rods are clear

I have a set of stamped rockers on the way to replace the roller tips. I did notice some scaring on the one with the bad ball.

 

Lifter oiling hole? Seems to be the only thing left.

 

This sounds as if the pushrods was not seated in the lifter but sitting on the edge ...

 

Did you try priming the engine with it all together. That would confirm if oil supply was the issue?

 

Fairly certain it was positioned properly. I had run it for a couple minutes and actually saw it moving thru the fill hole when I had the valve cover on.

 

No didn’t take the dist out. Was attempting to run it to check oil flow when the rocker went sideways

 

I'm starting to think the lifter is failing.

 

I'd see if you could stick a magnet through the push rod hole and pull the lifters out without taking the intake off to see if oil is flowing in the lifter bores.

 

Well, the lifters won't fit through the pushrod areas but can definitely come out through the distributor hole. Pull out of the bores with a magnet, manipulate to the dist hole and pull em out. #7 should be easy to retrieve.

 

Correct. I was just saying to pull them out and set them in the valley and crank it and see if any oil comes out of the bores, and yes, you can get them out through the distributor hole if needed.

 

I'm putting stock rockers on my 406 detune. Glad I did not go roller tip.

 

Found the problem. 4 lifters missing retaining clips

 

Very happy you found it! And it appears maybe that it survived without major carnage!


-rick

 

Do you know who made the lifters?

 

Perhaps. I will be pulling the motor to find the missing pieces

 

Comp Cams. They were part of a cam shaft spring, timing chain etc set.
Not sure why they decided to go after 30k miles. The motor is in a 4 speed 72 Blazer that I mostly use to tow a camper. I don’t think it ever gets above 3500rpm or 65mph Definitely not trying to win any races with it.

 

Called Comp Cams, they had no idea what could have caused this. Guy I talked to was pretty good, said if I had purchased thru them instead of Jegs he'd write up an RMA right away. Suggested that I call Jegs to see what they could do. Jegs thought it was nuts after 8 years they would think I would get warranty which is fair.

So Im looking to replace the cam shaft and lifters. Does anyone have any suggestions for a brand? Not sure if I can trust Comp stuff anymore

 

I had an old Crane cam lose a lobe. I bought a new E-brock RPM cam (part of their heads/intake/cam kit) and had issues with their cam instantly. They replaced the cam and exact same problem. At that point E-brock claimed the issue was with my engine and not their cam. I then bought a Comp Cam, installed it and ... perfect, no issues.

That being said, if the bottoms of all your Comp lifters show normal wear (suggesting the cam wasn't damaged), I'd just drop in some new lifters, break them in and run it. As for the shrapnel ... I'd attempt to retrieve and account for all of it without engine removal. Drag a strong magnet along the bottom of your oil pan in hopes that you can move stuff to the drain hole. If there are a few bits missing, you could glue the magnet to the bottom of the pan, close to the drain hole. I am assuming the clips are magnetic of course.

I will happily suggest you NOT buy an E-brock cam

To be clear, my issues were with a SBC.

 

Tech said I would need a new cam because both the lifters and cam wear to each other, but they are in the business of selling parts

 

Howards has a no fault full replacement warranty for Howards cams , I've been using Elgin cam & lifters for 25 years ( changed to a different grind about 10 years ago) ,no problems , had a summit cam & lifters in another vehicle for about 30 years , no troubles .
Use only ISKY rev- lube on your new setup.
Competition Products are good to deal with .